System configuration¶
When NumPy is built, information about system configuration is
recorded, and is made available for extension modules using NumPy’s C
API. These are mostly defined in numpyconfig.h (included in
ndarrayobject.h). The public symbols are prefixed by NPY_*.
NumPy also offers some functions for querying information about the
platform in use.
For private use, NumPy also constructs a config.h in the NumPy
include directory, which is not exported by NumPy (that is a python
extension which use the numpy C API will not see those symbols), to
avoid namespace pollution.
Data type sizes¶
The NPY_SIZEOF_{CTYPE} constants are defined so that sizeof
information is available to the pre-processor.
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NPY_SIZEOF_SHORT¶
sizeof(short)
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NPY_SIZEOF_INT¶
sizeof(int)
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NPY_SIZEOF_LONG¶
sizeof(long)
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NPY_SIZEOF_LONGLONG¶
sizeof(longlong) where longlong is defined appropriately on the platform.
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NPY_SIZEOF_PY_LONG_LONG¶
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NPY_SIZEOF_FLOAT¶
sizeof(float)
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NPY_SIZEOF_DOUBLE¶
sizeof(double)
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NPY_SIZEOF_LONG_DOUBLE¶
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NPY_SIZEOF_LONGDOUBLE¶
sizeof(longdouble)
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NPY_SIZEOF_PY_INTPTR_T¶
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NPY_SIZEOF_INTP¶
Size of a pointer on this platform (sizeof(void *))
Platform information¶
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NPY_CPU_X86¶
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NPY_CPU_AMD64¶
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NPY_CPU_IA64¶
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NPY_CPU_PPC¶
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NPY_CPU_PPC64¶
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NPY_CPU_SPARC¶
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NPY_CPU_SPARC64¶
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NPY_CPU_S390¶
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NPY_CPU_PARISC¶
New in version 1.3.0.
CPU architecture of the platform; only one of the above is defined.
Defined in
numpy/npy_cpu.h
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NPY_LITTLE_ENDIAN¶
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NPY_BIG_ENDIAN¶
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NPY_BYTE_ORDER¶
New in version 1.3.0.
Portable alternatives to the
endian.hmacros of GNU Libc. If big endian,NPY_BYTE_ORDER==NPY_BIG_ENDIAN, and similarly for little endian architectures.Defined in
numpy/npy_endian.h.
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int PyArray_GetEndianness()¶
New in version 1.3.0.
Returns the endianness of the current platform. One of
NPY_CPU_BIG,NPY_CPU_LITTLE, orNPY_CPU_UNKNOWN_ENDIAN.-
NPY_CPU_BIG¶
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NPY_CPU_LITTLE¶
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NPY_CPU_UNKNOWN_ENDIAN¶
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NPY_CPU_BIG¶